What is the general formula for calculation of % of drug content in any particular dosage form by HPLC method? Each pharmacopoeia and Individual product monograph has their own different formulae by considering the following parameters.
Area of standard
Area of sample
Weight of Standard
Weight of sample
Dilution Factor
% purity of Working Standard
LOD or Water Content
Average weight
But is there any specific or general formula which is applicable to all products?
Area of Sample X Wt. of Std X Potency of Std X Dilution Factor
% of content = -------------------------------------------------------------X 100
Peak Area of Std X Wt. of Sample X 100 X Avg. Wt
Thank you Subrata. What about if we don't have the average weight? In case we have directly used the tablets to prepare sample without crushing?
We can crush the tablets then we can take powder by calculating equivalent weight. then we can for sample preparation.
Abhishek, if you want to calculate the content uniformity of your preparation, then pharmacopoeia usually suggest to carry on the analysis as per your mentioned approach. But in case of "% of content analysis" or "content per tablet measurement", you should crush at least 20 tablets in a mortar and pestle, and then you should transfer a desired quantity of that finely powdered sample to a container. Before that, you have to calculate the average weight of that batch.
please how do i calculate the percentage label claim of a drug whose label concentration is 10 microgram per mL, but my assay gives a concentration of 5 microgram per mL. please i need a formula for this thanks.
%Assay= peak area SPl/ Peak Ara Std X Wt.of Std/Wt of sample X Dilution factor (If any) X 100
How to do assay for an injectable solution whose label claim is 32mg/0.4ml( highly concentrated)?
- Badges
- Science method